Plastic pipe fitting and closure

ABSTRACT

A cleanout for a plastic pipe system which includes a threadless socket and a threadless plug fitted in sealing relation in said socket and interconnected to prevent internal forces from displacing the plug. The socket and plug can be utilized in a pipe system for other purposes than that of a cleanout.

United States Patent Williams is] 3,677,301 [451 July 18, 1972 [54]PLASTIC PIPE FITTING AND CLOSURE [72] inventor: Robert M. Williams,Davison, Mich.

[73] Assignee: Genova Products, Davidson, Mich.

221 Filed: April 21, 1970 i 211 App]. 180.: 30,433

[52] US. Cl ..l38/92, 138/89, 220/40,

' 138/96 [51] Int. (l I 16] 55/10 [58] Field of Search l38/92, 89, 96;220/40 [56] References Cited UNITED STATES PATENTS 3,148,708 9/ l 964Panella 138/89 2,145,077 1/1939 'Fan',

3,065,767 11/1962 Topf 2,356,987 8/1944 Gallap 8,148,798 9/1964 Brown.1ss/s9x 2,607,045 8/1952 11101115.... .l38/89X 1,592,382 7/1926 Munn..-l38/89 1,884,165 10/1952 Otis ...l38/89X 3,401,842 9/1968 Morrison..22o/4ox FOREIGN PATENTS ORAPPLICATIONS 7 101,570 4/1954 Great Britain1138/89 Primary ExaminerHerbert F. Ross Attorney-Olsen and Stephenson 57ABSTRACT A cleanout for a plastic pipe system which includes athreadless socket and a threadless plug fitted in sealing relation insaid-socket and interconnected to prevent internal forces fromdisplacing the plug. The socket and plug can be utilized in a pipesystem for other purposes than that of a cleanout.

2Claims,5DrawingHgures PATENTEUJULIBIBIZ 3'577'301 v INVENTOR ROBERT MWILLIAMS PLASTIC PIPE FITTING AND CLOSURE BACKGROUND OF THE INVENTIONThe present invention relates to organic plastic pipe systems, andparticularly to an access fitting and closure for the system. It hasbeen conventional practice in pipe fittings, whether metal or plastic,to provide an internally threaded fitting and an externally threadedplug when it has been desirable or necessary to provide access to thesystem for cleanouts, pressure testing, or the like. This has beenespecially true in drain, waste and vent applications. Such accessfittings normally require threaded sealants to assure proper sealing ofthe system from the environment, and also require tools for removing andreinstalling the plugs.

SUMMARY OF THE INVENTION The present invention has overcome certainshortcomings of the prior art, and has provided an access fitting andclosure which are especially adapted for use in organic plastic pipesystems. The invention involves the use of an unthreaded locking plugfitted into an unthreaded socket which opens to the interior of the pipesystem. An appropriate sealing ring encircles the plug to provide aneffective seal between the plug and the socket. Also, suitableinterlocking elements are carried by the plug and the socket so thatafter the plug is inserted in place, it can be turned to a lockedposition which will prevent displacement of the plug by internal forcesfrom within the system.

According to one form of the present invention a threadless socket isprovided having a cylindrical internal bore. A threadless cylindricalplug is inserted into the bore, said plug having an annular groove inits outer cylindrical surface in which a sealing ring is seated insealing engagement with the internal bore of the socket. The socket hasa locking lug projecting radially outwardly from its outer surface, andthe plug has a lug retainer projecting radially outwardly from its outersurface and then projecting axially rearward beyond the locking lug. Theretainer has in its axially directed portion a circumferentiallydirected slot which is open at one end to receive the lug when the plugis turned in its inserted position relative to the socket.

Thus, it is an object of the present invention to provide an improvedaccess fitting and closure for a plastic pipe system.

Other objects of this invention will appear in the following descriptionand appended claims, reference being had to the accompanying drawingsforming a part of this specification wherein like reference charactersdesignate corresponding parts in the several views.

BRIEF DESCRIPTION OF THE DRAWING DESCRIPTION OF THE PREFERRED EMBODIMENTBefore explaining the present invention in detail, it is to beunderstood that the invention is not limited in its application to thedetails of construction and arrangement of parts illus-- trated in theaccompanying drawing, since the invention is capable of otherembodiments and of being practiced or carried out in various ways. Also,it is to be understood that the phraseology or terminology employedherein is for the purpose of description and not of limitation.

Referring now to the drawings, the invention will be described ingreater detail. The cleanout fitting and closure includes a segment of aplastic pipe 12 having at its end a threadless cylindrical bore 14defining a socket 16 having an inner beveled seat 17, and a plasticthreadless plug 18 having a cylindrical portion 20 closed at its innerend 21 and beveled so that the inner end 21 can fit against the beveledseat 17. The cylindrical surface 20 has an annular groove 22 therein inwhich is seated a sealing element 24, preferably a resilient O- ring. Adiametral flange 25 extends the length of the plug 18 to rigidify thesame and, if desired, for turning the plug.

The socket 16 has a pair of diametrically opposed, radially outwardlyprojecting lugs 26 located adjacent to theouter end 28. The plug 18 hasa pair of diametrically opposite, radially outwardly projecting lugretainers 30 including a first radially outwardly projecting portion 32which is adapted to seat on the end 28 of the socket 16, and an axiallyprojecting portion 34 which extends axially inwardly so as to overliethe outer surface of the socket 16. Each axially extending portion 34includes a slot 36 which opens in a generally circumferential directionto receive a lug 26 after the plug 18 has been pressed in place inseated relation in the socket 16 and turned relative to the socket 16.By virtue of this arrangement, the plug 18 can be fitted into the socketl6 and can be turned relative thereto to the position shown in FIG. 2,whereby internal pressures will be unable to dislodge the plug 18. Asshown best in FIG. 3, when the plug 18 is in its inserted position, theO-ring 24 will be-in sealing engagement with the inner cylindricalsurface of the socket 16 so that an effective seal is provided.

When it is desired to remove the plug from the socket 16, this canreadily be accomplished merely by manually engaging the lug retainers 30or the diametral flange 25 and turning the plug 18 relative to thesocket 16 until the lugs 26 are free from being enclosed by the slot 36,and the plug 18 can then be pulled from the socket l6 merely by pullingon the retainers 30. Thus, an improved and simple fitting and closure 19has been provided which will enable easy access to be had to theinterior of the pipe system, and wherein such access can be gainedwithout the need of special tools for removing the plug. Also, when theplug is in place a very effective seal is provided.

As shown in FIGS. 4 and 5, the present invention can be embodied inother types of fittings. As there shown, the invention is embodied in atee-fitting 38 which has a threadless cylindrical bore 40 defining asocket 42 in which is secured a threadless plug 44. The plug 44 isessentially the same as the plug 18, except that the plug 44 has anannular lip 46 which is seated on the outer end of the pipe segment orsocket 40, and in addition, plug 44 has a contour to its closed innerend 48 which conforms to the cylindrical surface 50 defining thepassageway through fitting 38. Thus, the plug 44 assures a smoothcontinuous flow passageway through fitting 38, and the lug retainers 52,when in interlocking engagement with the lugs (not shown) will assurethat the surface 48 is properly oriented relative to the surface 50 toprovide such smooth continuous flow passageway.

It is claimed: l

1. In a plastic piping system, a threadless socket having a cylindricalinternal bore, a threadless tubular cylindrical plug inserted into saidbore, and having a closed inner end and a diametral reinforcing flangeintegral with the inner end and extending the length of the plug, saidplug having an annular groove in its outer cylindrical surface, asealing ring in said groove in sealing engagement with said internalbore, said socket having a locking lug projecting radially outward fromits outer surface, and said plug having a lug retainer projectingradially outwardly beyond said outer surface of the socket and the stemportion of a tee-fitting having ,a passageway therethrough, and saidplug has a closed inner end conforming to the shape of the inner surfaceof the passageway through the fitting when the plug is in its retainedposition.

2. The combination of a pipe fitting and a closure plug for a pipingsystem, said fitting having a through-passageway and a laterallydirected socket defining a threadless cylindrical bore in communicationwith said passageway,-said closure plug having a cylindrical portionextending into said cylindrical bore in sealing relationship, the outerend of said plug having at least one projection extending over a portionof the outer surface of said socket, means on the outer surface of said

1. In a plastic piping syStem, a threadless socket having a cylindricalinternal bore, a threadless tubular cylindrical plug inserted into saidbore, and having a closed inner end and a diametral reinforcing flangeintegral with the inner end and extending the length of the plug, saidplug having an annular groove in its outer cylindrical surface, asealing ring in said groove in sealing engagement with said internalbore, said socket having a locking lug projecting radially outward fromits outer surface, and said plug having a lug retainer projectingradially outwardly beyond said outer surface of the socket and axiallybeyond said locking lug, said retainer having in its axially directedportion a circumferentially directed slot which is open at one end toreceive said lug when said lug is turned in its inserted positionrelative to said socket, said socket being the stem portion of atee-fitting having a passageway therethrough, and said plug has a closedinner end conforming to the shape of the inner surface of the passagewaythrough the fitting when the plug is in its retained position.
 2. Thecombination of a pipe fitting and a closure plug for a piping system,said fitting having a through-passageway and a laterally directed socketdefining a threadless cylindrical bore in communication with saidpassageway, said closure plug having a cylindrical portion extendinginto said cylindrical bore in sealing relationship, the outer end ofsaid plug having at least one projection extending over a portion of theouter surface of said socket, means on the outer surface of said socketinterlocked with said projection to prevent axial outward movement ofthe plug and to position the plug radially when said means and saidprojection are interlocked, said plug having a closed inner endconforming to the shape of the inner surface of the through-passagewaywhen the plug is in its interlocked position so that a smooth continuouswall surface is provided in said through-passageway.